1.9 KiB
NES/Famicom-oriented modules
nes_hardware
The nes_hardware module is imported automatically on NES targets.
TODO
nes_mmc4
The nes_mmc4 module is imported automatically on the NES MMC4 target.
and contains routines related to MMC4 bankswitching.
void set_prg_bank(byte a)
Changes the $8000-$BFFF PRG bank.
void set_chr_bank0(byte a)
Changes the CHR bank 0 ($0000-$0fff in the PPU memory space).
The high nibble (0 or 1) selects between chrrom0 and chrrom1 segments.
The low nibble L (0-$F) selects a 4K-aligned address in the segment ($L000).
void set_chr_bank1(byte a)
Changes the CHR bank 1 ($1000-$1fff in the PPU memory space).
The high nibble (0 or 1) selects between chrrom0 and chrrom1 segments.
The low nibble L (0-$F) selects a 4K-aligned address in the segment ($L000).
void set_vertical_mirroring()
Switches nametable mirroring to vertical.
void set_horizontal_mirroring()
Switches nametable mirroring to horizontal.
nes_joy
Provides an interface for reading joypads that is compatible with the joy module.
alias input_a = input_btn
1 if A button pressed, 0 id not pressed.
byte input_b
1 if B button pressed, 0 id not pressed.
byte input_select
1 if Select button pressed, 0 id not pressed.
byte input_start
1 if Start button pressed, 0 id not pressed.
void read_joy1()
Reads the joypad from the port 1.
void read_joy2()
Reads the joypad from the port 2.
void read_also_joy1()
Reads the joypad from the port 1 and adds its readouts to the current readouts.
void read_also_joy2()
Reads the joypad from the port 2 and adds its readouts to the current readouts.
void nes_reset_joy()
Resets the state variables.
Unlike reset_joy, this resets all the NES button states.
nes_joy1_default
Defines the joystick in port 1 as the default joystick.